1. Field of the Invention
The present invention relates to archery arrow nocks, and more particularly to arrow nocks designed to yield superior ballistic arrow performance and to facilitate arrow recovery.
Archers all wish to have maximum control over the flight of their arrows. They often find it desirable to customize their arrows depending upon the targets involved or game hunted, and they seek reliability in their equipment and consistency in its performance.
Satisfactory arrow flight involves: consistency, accuracy, distance, speed of travel, drop, reaction to cross-wind, reaction to environment and target penetration.
It is well appreciated that arrow flight is affected by the structure of the arrow and by the structure and nature of the launching bow. Simplistically, this is reflected in the use of properly weighted, straight, balanced arrows cleanly launched by a well-strung taut bowstring. Satisfactory flight is determined by the equipment, both during launch and after arrow release. There are many arrow and bow designs having the objectives of improving arrow ballistics, improving launch, controlling flight, extending distance, and enhancing target penetration. There are also many structures adapted for inclusion or attachment to arrow shafts and bows to achieve these objectives, either independently or in conjunction with structural modifications of the launching bow.
It is recognized that the flight of an arrow is stabilized by rotation. This is commonly imparted by fletching affixed to the arrow which induces rotation responsive to air movement during arrow trajectory. Alternatively, arrow rotation may be induced before or during arrow launch by providing torsional force on the arrow shaft. Thus, it is understood that the arrow flight may be determined during the control exerted over the arrow by the bowstring upon initial engagement, during bowstring release, during bowstring pressure before launch, and as the arrow commences flight when the bowstring begins relaxation.
As a practical matter, it is also important to recognize the economic benefit of having arrows that can be used with a variety of bows. Obviously it is also desirable to be able to reuse spent arrows, something that can be facilitated by appropriate tracking means, damage resistant and/or easily repaired or replaced components.
2. Description of Related Art
The prior art is replete with flight stabilizers, arrow accelerating devices and special nocks for attachment to specially designed arrows. Many devices are disclosed for attachment to arrows to track flight and detect their landing sites.
U.S. Pat. No. 4,900,037 to Miller suggests that increased arrow acceleration can be obtained by inserting a spring within telescoping sleeves at the rear of a hollow arrow shaft. During bowstring draw, this spring is extended. Upon bowstring release, energy is stored by compressing the spring. This energy is released by spring extension as the arrow leaves the bow.
U.S. Pat. No. 5,971,875 to Hill discloses a notched spinner tube having spiraled grooves on its outer surface to engage dimples on the inside of an arrow shaft that has been deformed by a special tool. When the arrow is launched, the spinner tube is forced into the arrow shaft and the spiral grooves of the spinner tube act upon the dimples on the arrow shaft causing the arrow to rotate.
U.S. Pat. No. 6,478,700 to Hartman discloses an arrow spin drive having a screw shaft containing cam surfaces that cooperate with a guide inside a hollow arrow shaft to impart rotation when the arrow is launched.
U.S. Pat. No. 6,203,457 to Snook discloses a removable nock having a special curved notch into which the bowstring is placed. The notch has a twisted opening so that as the arrow leaves the bowstring, a torsional force is imparted.
U.S. Pat. No. 6,877,500 to Hollers and Edwards discloses a helically slotted spin tube attached to a bow for imparting arrow rotation as the arrow traverses the tube during launch. A nock drive assembly cooperates with the bow spin tube. When the bowstring is released, the nock drive assembly moves laterally within the spin tube while a nock pin travels along the helical slots imparting rotation to the arrow.
Among other patents disclosing arrangements for inducing arrow rotation, one may note U.S. Pat. No. 4,111,424 to Schreiber et al, U.S. Pat. No. 5,846,147 to Basik, and U.S. Pat. No. 6,595,880 to Becker. Of additional possible interest with respect to nocks designed to effect arrow performance, one may note U.S. Pat. No. 4,900,037 to Miller, U.S. Pat. No. 5,134,552 to Call and Denen, and U.S. Pat. No. 5,186,470 to Easton and Filice.
While the prior art contains disclosures of diverse archery equipment calculated to improve arrow performance, none of this disclosed equipment, shows or suggests the structure of the arrow nocks embodying the present invention, or results attainable through the use of these nocks. Nor is there any disclosure of arrow nocks containing elements assembled in the manner of the present invention which can be applied to conventional arrows in the field to accommodate perceived field conditions.